Placebos probably work for problems related to neural system (the less you are nervous the more healthy you are).

Taking Steve Jobs as an example here is a bad way to get healthy. Steve Jobs was simply used to listening to (back then) always smarter engineers. Medicine, however, wasn’t revolutionised the same way.

Steve Jobs apparently tried a homepathic diet in lieu of surgery for quite a while. He did have the less aggressive type of pancreatic cancer (islet cell carcinoma vs adenocarcinoma).